TY - JOUR
T1 - Tidal heating models for the radii of the inflated transiting giant planets WASP-4b, WASP-6b, WASP-12b, WASP-15b, and TrES-4
AU - Ibgui, Laurent
AU - Burrows, Adam
AU - Spiegel, David S.
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2010
Y1 - 2010
N2 - In order to explain the inflated radii of some transiting extrasolar giant planets, we investigate a tidal heating scenario for the inflated planets WASP-4b, WASP-6b, WASP-12b, WASP-15b, and TrES-4. To do so, we assume that they retain a nonzero eccentricity, possibly by dint of continuing interaction with a third body. We calculate the amount of extra heating in the envelope that is then required to fit the radius of each planet, and we explore how this additional power depends on the planetary atmospheric opacity and on the mass of a heavy-element central core. There is a degeneracy between the core mass M core and the heating . Therefore, in the case of tidal heating, there is for each planet a range of {M core, e 2/ Q′p} that can lead to the same radius, where Q′p is the tidal dissipation factor and e is the eccentricity. With this in mind, we also investigate the case of the non-inflated planet HAT-P-12b, which can admit solutions combining a heavy-element core and tidal heating. A substantial improvement of the measured eccentricities of such planetary systems could simplify this degeneracy by linking the two unknown parameters {M core, Q′p}. Further independent constraints on either of these parameters would, through our calculations, constrain the other.
AB - In order to explain the inflated radii of some transiting extrasolar giant planets, we investigate a tidal heating scenario for the inflated planets WASP-4b, WASP-6b, WASP-12b, WASP-15b, and TrES-4. To do so, we assume that they retain a nonzero eccentricity, possibly by dint of continuing interaction with a third body. We calculate the amount of extra heating in the envelope that is then required to fit the radius of each planet, and we explore how this additional power depends on the planetary atmospheric opacity and on the mass of a heavy-element central core. There is a degeneracy between the core mass M core and the heating . Therefore, in the case of tidal heating, there is for each planet a range of {M core, e 2/ Q′p} that can lead to the same radius, where Q′p is the tidal dissipation factor and e is the eccentricity. With this in mind, we also investigate the case of the non-inflated planet HAT-P-12b, which can admit solutions combining a heavy-element core and tidal heating. A substantial improvement of the measured eccentricities of such planetary systems could simplify this degeneracy by linking the two unknown parameters {M core, Q′p}. Further independent constraints on either of these parameters would, through our calculations, constrain the other.
KW - Planetary systems
KW - Planets and satellites: general
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U2 - 10.1088/0004-637X/713/2/751
DO - 10.1088/0004-637X/713/2/751
M3 - Article
AN - SCOPUS:77950269162
VL - 713
SP - 751
EP - 763
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
ER -